Purpose:　In　a　previous　study,　the　authors　verified　the　protective　efficacy　of　adipose-derived　stem　cells　(ADSCs)　on　the　prevention　of　salivary　gland　(SG)　damage　induced　by　irradiation　in　mice.　As　a　critical　step　before　implementation　in　clinical　practice,　the　present　study　investigated　the　protective　effect　of　ADSCs　in　a　miniature　pig　SG　model,　because　miniature　pigs　share　many　characteristics　with　humans.　Materials　and　Methods:　Third-passage　autologous　ADSCs　at　a　concentration　of　4　x　10(6)　cells/mL　were　transplanted　by　intraglandular　injection　into　parotid　glands　(PGs)　immediately　after　local　irradiation　at　a　single　dose　of　20　Gy.　The　injection　process　was　repeated　twice　a　week　for　6　consecutive　weeks.　At　12　weeks　after　irradiation,　functional　and　histologic　evaluations　were　performed　by　measuring　salivary　flow　rate　(SFR)　and　hematoxylin　and　eosin　and　periodic　acid-Schiff　staining.　Immunohistochemical　and　transmission　electron　microscopic　examinations　also　were　conducted　to　evaluate　amylase　(AMY)　production,　microvessel　density　(MVD),　and　microstructural　changes.　Results:　The　irradiated　PGs　showed　remarkable　decreases　in　SFR,　AMY　production,　and　MVD.　However,　transplantation　of　ADSCs　alleviated　irradiated　PG　morphology　and　function　by　preserving　more　functional　acinar　cells　and　increasing　SFR　and　AMY　production.　In　addition,　greater　MVD　was　observed　in　the　ADSC-treated　group　than　in　the　irradiated　group.　Conclusions:　These　results　indicated　that　intraglandular　transplantation　of　autologous　ADSCs　is　an　effective　method　to　protect　PGs　against　damage　from　irradiation　in　miniature　pigs,　which　might　have　clinic　application　in　the　future.　(C)　2016　American　Association　of　Oral　and　Maxillofacial　Surgeons